The simplest thing makes a word of difference

BestClassEver.m

//Author: https://github.com/TouchCode
//Code File: https://github.com/TouchCode/TouchUI/blob/master/Source/Views/CBetterAlertView.m

#import <UIKit/UIKit.h>

@interface CBetterAlertView : UIAlertView {
	id userInfo;
}

@property (readwrite, nonatomic, retain) id userInfo;

@end

@implementation CBetterAlertView

@synthesize userInfo;

- (void) dealloc {
	self.userInfo = NULL;
	[super dealloc];
}

@end